Discovery of generalizable TBI phenotypes using multivariate time-series clustering.

Traumatic Brain Injury (TBI) presents a broad spectrum of clinical presentations and outcomes due to its inherent heterogeneity, leading to diverse recovery trajectories and varied therapeutic responses. While many studies have delved into TBI phenotyping for distinct patient populations, identifying TBI phenotypes that consistently generalize across various settings and populations remains a critical research gap. Our research addresses this by employing multivariate time-series clustering to unveil TBI's dynamic intricates. Utilizing a self-supervised learning-based approach to clustering multivariate time-Series data with missing values (SLAC-Time), we analyzed both the research-centric TRACK-TBI and the real-world MIMIC-IV datasets. Remarkably, the optimal hyperparameters of SLAC-Time and the ideal number of clusters remained consistent across these datasets, underscoring SLAC-Time's stability across heterogeneous datasets. Our analysis revealed three generalizable TBI phenotypes (α, ß, and γ), each exhibiting distinct non-temporal features during emergency department visits, and temporal feature profiles throughout ICU stays. Specifically, phenotype α represents mild TBI with a remarkably consistent clinical presentation. In contrast, phenotype ß signifies severe TBI with diverse clinical manifestations, and phenotype γ represents a moderate TBI profile in terms of severity and clinical diversity. Age is a significant determinant of TBI outcomes, with older cohorts recording higher mortality rates. Importantly, while certain features varied by age, the core characteristics of TBI manifestations tied to each phenotype remain consistent across diverse populations.

Three-corner arthrodesis for scapholunate and scaphoid nonunion advanced collapsed wrists: outcomes at long term follow-ups.

OBJECTIVES: This study aimed to assess clinical, functional and radiological outcomes after three-corner arthrodesis in patients suffering from symptomatic scapholunate or scaphoid non-union advanced collapsed wrists. We hypothesised that three-corner arthrodesis provided satisfactory clinical and radiological results in the long term. MATERIAL AND METHODS: This was a retrospective study of 13 patients (14 wrists) who underwent a three-corner arthrodesis between March 2004 and January 2019 with a mean follow-up of 6,7 years. Clinical assessment consisted of wrist motion, grip strength, pain and functional scores (Quick-DASH, PRWE, MWS). All complications and surgical revisions were investigated. Radiographic assessment searched for union, evaluated carpal height and ulnar translation, lunate tilt and occurrence of radio-lunate arthritis. RESULTS: At the last follow-up Quick-DASH and PRWE scores were 24,87(± 17.2) and 47.4 (± 26.9) respectively and were significantly improved. Wrist motion was 35°, 32°, 10° et 24° of flexion, extension, radial and ulnar deviation respectively. Union was obtained for 13 (92,9%) wrists. The mean radiolunate angle was 11° (-17°-34°). Three patients needed reintervention, which 2 consisted of total wrist arthrodesis due to persisting pain. Mild signs of radio-lunate arthritis were found in three patients. CONCLUSION: Three-corner arthrodesis seemed to provide satisfactory long-term functional outcomes. The union rate was high and even patients with signs of radio-lunate arthritis still had improved outcomes at the last follow-up. It could be a part of surgical options in wrists with radio- and midcarpal arthritis, among other procedures.

Perilunate Fracture-Dislocation: Results at Mean Follow-Up of 7 Years after ORIF.

Background: Perilunate fracture-dislocations are frequently associated with a high risk of developing post-traumatic arthritis. Current studies indicate that during mid-term follow-ups, radiological signs of arthritis do not appear to correspond with functional score. The aim of this study was to assess the occurrence of posttraumatic arthritis and the wrist function after perilunate dislocations (PLD) and fracture dislocations at a mid-term follow-up of 7 years. Methods: We report the clinical and radiological outcomes of 17 wrists treated for PLD or fracture-dislocation by open reduction and internal fixation through a dorsal approach with dorsal ligament repair. Functional outcomes were evaluated using the short version of the Quick Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH), the Patient-Rated Wrist Evaluation questionnaire (PRWE) and the Mayo Wrist Score (MWS). Results of radiographs were assessed using the Herzberg Radiological Scoring Chart. Results: The MWS showed five excellent, five good, five fair and two poor results with an average score of 81%. Radiological analysis using the Herzberg classification revealed midcarpal and/or radiocarpal arthritis in 65% of cases, lunate collapse in 59% and an increase in the mean ulnar translocation ratio in 53% of the cases. Complications included one case of lunate osteonecrosis and one case of stage 3 scapholunate advanced collapse that required revision surgery. Conclusions: Although the clinical and functional outcomes are favourable at mid-term follow-up, radiological evaluation shows a progression towards osteoarthritis (OA). Further research is warranted to refine treatment strategies and investigate factors influencing the development of OA. Level of Evidence: Level IV (Therapeutic).

A module involving HIGH LEAF TEMPERATURE1 controls instantaneous water use efficiency.

Drought stress inhibits plant growth and agricultural production. Improving plant instantaneous water use efficiency (iWUE), which is strictly regulated by stomata, is an effective way to cope with drought stress. However, the mechanisms of iWUE regulation are poorly understood. Through genetic screening for suppressors of mpk12-4, an Arabidopsis (Arabidopsis thaliana) mutant with a major iWUE quantitative trait locus gene MITOGEN-ACTIVATED PROTEIN KINASE12 deleted, we identified HIGH LEAF TEMPERATURE1 (HT1). Genetic interaction and physiological analyses showed that MPK12 controls iWUE through multiple modules in a high CO2-induced stomatal closing pathway that regulate SLOW ANION CHANNEL-ASSOCIATED1 (SLAC1) activity. HT1 acts downstream of MPK12, whereas OPEN STOMATA1 (OST1) and GUARD CELL HYDROGEN PEROXIDE-RESISTANT1 (GHR1) function downstream of HT1 by activating SLAC1 in iWUE. Photosynthetic-CO2 response curves and biomass analyses under different water-supply conditions showed that HT1 dysfunction improved iWUE and also increased plant growth capacity, and products of HT1 putative orthologs from Brassica (Brassica napus) and rice (Oryza sativa) exhibited functions similar to that of Arabidopsis HT1 in iWUE and the CO2-signaling pathway. Our study revealed the mechanism of MPK12-mediated iWUE regulation in Arabidopsis and provided insight into the internal relationship between iWUE and CO2 signaling in guard cells and a potential target for improving crop iWUE and drought tolerance.

Scapholunate Advanced Collapse (SLAC) and Scaphoid Nonunion Advanced Collapse (SNAC): A Review of Treatment Options for Stage II.

Scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) represent clinical entities identified by a pattern of predictable degenerative changes. They are the most common causes of wrist arthritis. Both entities can remain asymptomatic for many years and may go undiagnosed. Diagnosis is usually confirmed through clinical examination, which reveals progressive wrist pain and instability. Radiographically, degenerative changes in the radiocarpal and midcarpal joints are present, as well as nonunion of the scaphoid fracture in SNAC. The management differs according to the stage. Particularly in this review article, we reviewed the treatment options for stage II SLAC and SNAC wrist. In addition to the well-described surgical techniques such as proximal row carpectomy and four-corner fusion, alternatives such as capitolunate arthrodesis, three-corner fusion, and soft tissue procedures like capsulodesis and tenodesis are available. Proximal row carpectomy and partial arthrodeses yield comparable results. Soft tissue procedures are viable alternatives and are preferred in younger patients to avoid early salvage operations.

The Sensitivity of the Scapholunate Interval and Bony Landmarks to Wrist Rotation on Posteroanterior Radiographs.

BACKGROUND: The objective of this study was to examine the effect of wrist rotation on the scapholunate interval in the posteroanterior radiograph and to identify radiographic landmarks on the posteroanterior projection that can be used to assess position. METHODS: Eleven healthy cadaveric wrists were radiographed in the neutral position and subsequently were rotated and imaged from 30° pronation to 30° supination in 10° intervals. At each interval, the scapholunate interval was measured as well as the following landmarks: (1) the visible perimeter of the base of the hook of the hamate; (2) the radial-ulnar distribution of the dorsal nonarticular surface of the distal third metacarpal head; (3) the radial-ulnar distribution of the pisiform about the longitudinal axis of the ulna; and (4) the overlap of the pisiform and triquetrum. RESULTS: The scapholunate interval was largest in the neutral position and linearly decreased by 34% for every 10° of pronation and decreased nonlinearly by 86% after the first 10° of supination. The appearance of the distal third metacarpal head was shown to be sensitive to both pronation and supination. The perimeter of the hook of the hamate and the distribution of the pisiform compared to the ulna were both shown to be sensitive to supination, whereas overlap of the pisiform and triquetrum was not shown to be sensitive to either direction of rotation. CONCLUSIONS: Our results highlight the significant effect of rotation on radiographic landmarks at the wrist, indicating that 10° of supination can drastically alter the developed radiograph.

Discovery of Generalizable TBI Phenotypes Using Multivariate Time-Series Clustering.

Traumatic Brain Injury (TBI) presents a broad spectrum of clinical presentations and outcomes due to its inherent heterogeneity, leading to diverse recovery trajectories and varied therapeutic responses. While many studies have delved into TBI phenotyping for distinct patient populations, identifying TBI phenotypes that consistently generalize across various settings and populations remains a critical research gap. Our research addresses this by employing multivariate time-series clustering to unveil TBI's dynamic intricates. Utilizing a self-supervised learning-based approach to clustering multivariate time-Series data with missing values (SLAC-Time), we analyzed both the research-centric TRACK-TBI and the real-world MIMIC-IV datasets. Remarkably, the optimal hyperparameters of SLAC-Time and the ideal number of clusters remained consistent across these datasets, underscoring SLAC-Time's stability across heterogeneous datasets. Our analysis revealed three generalizable TBI phenotypes (α, ß, and γ), each exhibiting distinct non-temporal features during emergency department visits, and temporal feature profiles throughout ICU stays. Specifically, phenotype α represents mild TBI with a remarkably consistent clinical presentation. In contrast, phenotype ß signifies severe TBI with diverse clinical manifestations, and phenotype γ represents a moderate TBI profile in terms of severity and clinical diversity. Age is a significant determinant of TBI outcomes, with older cohorts recording higher mortality rates. Importantly, while certain features varied by age, the core characteristics of TBI manifestations tied to each phenotype remain consistent across diverse populations.

Single- and Bicolumn Limited Intercarpal Fusion: A Solution for the SLAC or SNAC Wrist.

Background Single- or bicolumn limited intercarpal fusion, also called one- or two-column fusion, has been introduced as an alternative to four-corner fusion. The rationale behind this is obtaining less need for bone grafting and consequently improving the chances of the union. Method From August 2014 to October 2020, 45 consecutive patients (15 women), with a mean age of 58.4 years (range: 35-79), have been treated for scapholunate advanced collapse or scaphoid nonunion advanced collapse wrist. In 33 cases, the surgery was performed as two-column fusion, and in 12 cases as one-column fusion. The union was determined by a computed tomography (CT) scan or X-ray follow-up studies. The pain assessments (visual analog score: 0-100), range of motion (ROM), grip strength, and Quick Disabilities of the Arm, Shoulder, and Hand score were prospectively included. Results Of 45 patients, 43 were available for the follow-up, at a mean of 35 months (range: 12-68). All patients but two achieved union at a mean of 9.5 weeks (range: 5-25 weeks). Pain diminished from 60.3 (mean) preoperatively to 16.7 (mean) postoperatively ( p = 0.0001). Grip strength slightly increased from 28.2 KgF (mean) to 29 KgF (mean) (not significantly, p = 0.86). Quick Disability of the Arm, Shoulder, and Hand score improved from 39.5 (median) before the surgery to 11 (median) after the surgery ( p = 0.0004). The postoperative ROM of 62/37 degrees (mean) were recorded for total dorsovolar/radioulnar flexions, respectively. Three patients were converted to total wrist fusion and one to total wrist arthroplasty. One had a rearthrodesis to two-column fusion, which united. Conclusion One- and two-column fusion showed significant improvement in pain and function, with minimal impairment of the grip strength on the short- to mid-term follow-up. A union rate of 95% and an acceptable complication rate were achieved, without fusing all carpals. Level of Evidence Prospective, cohort study, level III.

Effects of a neuromuscular joint-protective exercise therapy program for treatment of wrist osteoarthritis: a randomized controlled trial.

BACKGROUND: Individuals with wrist osteoarthritis (OA) can suffer from pain, muscular weakness, and impaired motion of the wrist, which can reduce the quality of life. While there is strong evidence that all patients with OA should receive first-line treatment with education and exercises, this approach has not yet been proposed for individuals with wrist OA. Therefore, this trial aimed to evaluate the effectiveness of a first line neuromuscular joint-protective exercise therapy program compared to a training program with range of motion (ROM) exercises in patients with wrist OA. METHODS: In this randomized controlled trial (RCT), 48 patients with symptomatic and radiographically confirmed wrist OA were randomly allocated to a 12-week self-management program with either a neuromuscular joint-protective exercise therapy program (intervention group) or a training program with ROM exercises only (control group). Our primary outcome measure was the Patient-Rated Wrist Evaluation (PRWE) with secondary outcome measures of grip strength, range of wrist motion, the Numerical Pain Rating, Scale (NPRS), the Disabilities of the Arm, Shoulder, and Hand (DASH) and the Generalized Self-Efficacy Scale (GSES). The outcome measures were evaluated by a blinded assessor at baseline and 12 weeks. Between-groups differences were analyzed using the Mann-Whitney U test and within-group differences were analyzed with the Wilcoxon signed-rank test. RESULTS: A total of 41 participants were analyzed at 12 weeks. There were no significant differences in PRWE between the groups at 12 weeks (p = 0.27). However, DASH improved significantly in the intervention group compared to the control group (p = 0.02) and NPRS on load within the intervention group (p = 0.006). The difference in DASH should be interpreted with caution since it could be due to a non-significant increase (worsening) from baseline in the control group in combination with a non-significant decrease (improvement) in the intervention group. CONCLUSIONS: This RCT showed that the novel neuromuscular joint-protective exercise therapy program was not superior in reducing pain and improving function compared to a training program with ROM exercises at 12 weeks. Future research is warranted to evaluate the effectiveness of forthcoming exercise therapy treatment programs for patients with wrist OA. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05367817. Retrospectively registered on 10/05/2022. https://clinicaltrials.gov .

Usefulness of risk scores and predictors of atrial fibrillation recurrence after elective electrical cardioversion.

INTRODUCTION: Electrical cardioversion (ECV) is a frequently used procedure for restoring sinus rhythm in atrial fibrillation (AF); however, the rate of recurrence is high. The identification of patients at high risk of recurrence could influence the decision-making process. The present study evaluates the predictive value of risk scores in atrial fibrillation recurrence after elective electrical cardioversion. METHODS: Unicentric, observational, and prospective study of adult patients who have undergone an elective ECV as rhythm control strategy between July 2017 and September 2022. RESULTS: From the 283 analyzed patients (mean age 63.95 ± 10.76212, 74.9% male); 99 had paroxysmal AF (35%) and 159 (59%) presented AF recurrence during a follow-up of 6 months. In patients with post-ECV AF recurrence, the period of time from diagnosis until the performance of the procedure was longer (393 ± 891 vs. 195 ± 527, p = .02). No paroxysmal AF (71.3% vs. 57.8%, p = .02) and LA dilatation with >40 mL/m2 (35.9% vs. 23.3%, p = .02) volumes were more frequent within these patients. AF recurrence was more frequent in patients who had previous ECV (HR = 1.32; 95% CI: 1.12-2.35; p = .01) and more than 1 shock to recover sinus rhythm (HR = 1.62; 95% CI: 1.07-1.63; p = .01). The SLAC, ALARMEc, ATLAS, and CAAP-AF scores were statistically significant, although with a moderate predictive capacity for post-ECV recurrence. CONCLUSIONS: Risk scores analyzed showed a modest value predicting AF recurrence after ECV. Previous ECV, and greater difficulty in restoring SR were independent predictors of recurrence.

Comparison of proximal row carpectomy with RCPI® versus proximal row carpectomy with Eaton's capsular interposition in the management of advanced wrist osteoarthritis.

INTRODUCTION: Proximal row carpectomy (PRC) is one of the recommended techniques for managing wrist osteoarthritis, it implies the integrity of the lunate fossa of the radius and the proximal pole of the capitate. If PRC is not possible, it is suggested to consider combining it with a capsule interposition (such as Eaton's flap) or opting for intra- or radiocarpal arthrodesis. Another alternative is to combine capitate resurfacing with a pyrocarbon implant (RCPi®). The aims of this study was to assessed the results between proximal PRC+Eaton and those associated PRC+RCPi® for advanced wrist osteoarthritis. HYPOTHESIS: We hypothesized that there would be no differences in clinical or functional outcome between proximal row carpectomy associated with RCPI® and those associated with Eaton capsular flap. MATERIAL AND METHODS: It is a monocentric, retrospective, multi-operator study involving 83 wrists with osteoarthritis, included between January 2000 and December 2020 with a minimum follow-up period of 12 months. Thirty-nine patients underwent PRC+Eaton and 44 patients underwent RCPI® resurfacing. Data such as pain, flexion, extension and strength as well as functional scores (PRWE, Mayo and quick DASH) were collected from the patient files at the last check-up. RESULTS: Results were comparable between the two groups in terms pain (VAS), mobility (flexion and extension), strength (GRASP) and functional scores (PRWE, Mayo and quick DASH). Carpal height was better preserved in the PRC+RCPI® group, with a Youm and McMurtry index evaluated at 0.3 in the PRC+Eaton group compared to 0.4 in the PRC+RCPI® group (p-value<0.001). Radiocarpal arthrodesis was required in 16% of the PRC+Eaton group and 6.8% of the PRC+RCPI® group, with a statistically significant difference (p-value=0.023). DISCUSSION: This study reports clinical and functional results that suggest RCPI® is an interesting alternative and can be associated with proximal row carpectomy in advanced wrist osteoarthritis. LEVEL OF EVIDENCE: IV; retrospective study.

Lunocapitate versus four-corner fusion in scapholunate or scaphoid nonunion advanced collapse: a randomized controlled trial.

This pragmatic randomized controlled trial compared lunocapitate fusion (LCF) and four-corner fusion (4CF) for scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) in 64 patients. The primary outcome was change in grip strength from preoperative to 1 year postoperatively. The secondary outcomes were Disability of the Hand, Arm, and Shoulder score, Patient Rated Wrist Evaluation score, EuroQol-5D-3L, range of motion, key pinch strength and complications 12 months postoperatively. Grip strength improved only to a small extent and there was no difference between the groups. No differences were found in the secondary outcomes. In conclusion, LCF is not inferior to 4CF regarding strength, range of motion or patient-reported outcome measures.Level of evidence: I.

Radiologic Evolution after Scapholunate Dorsal Capsulodesis for Chronic Tears.

Background Many debates are still ongoing for the management of chronic scapholunate (SL) injuries. We have proposed an arthroscopic technique of dorsal capsulodesis with good clinical results. We now propose a radiological follow-up. Purpose To determine if arthroscopic dorsal capsulodesis can improve the radiographic SL angle and maintain this correction over time. Methods From January 2020 to January 2021, we included every patient with an SL instability and sorted them according to the European Wrist Arthroscopy Society (EWAS) classification. All patients had bilateral X-rays with a measurement of the radiolunate (RL) and SL angles for both the pathologic and healthy side. We also included patients with lunotriquetral or triangular fibrocartilage complex lesions. The exclusion criteria were the presence of arthritis and persistent intraoperative SL instability after capsulodesis. An arthroscopic dorsal capsulodesis was performed in all patients as originally described by Mathoulin. The RL and SL angles were then again measured on the immediate postoperative X-ray, and then again at 3, 6, and 12 months postoperatively. The statistical analysis was done using a paired Student's t -test with 145 degrees of freedom and α = 0.05. Results We included a total of 146 patients with a 1-year follow-up. Both the RL angle and the SL angles approach the healthy side at 12 months postoperatively. The RL angle has increased from -7.23 degrees to 4.37 degrees; the difference is still statistically significative, but it is almost equal to the healthy side (5.16 degrees). The SL angle has lowered from 74.55 to 54.95; the difference is still statistically and radiologically significative (6.788 degrees) but has been lowered by 74.3%. Conclusion This study shows that this technique can normalize the dorsal intercalated segment instability (DISI) over time without the need for any pinning or invasive ligament reconstructive surgery. Level of Evidence Level IV, cohort study. Clinical Relevance Dorsal capsulodesis should be considered in all reducible SL injuries, even when DISI is present.

A self-managed exercise therapy program for wrist osteoarthritis: study protocol for a randomized controlled trial.

BACKGROUND: Post-traumatic wrist osteoarthritis (OA) can eventually lead to pain, muscular weakness, and stiffness of the wrist, which can affect the function of the entire upper limb and reduce the quality of life. Although there is strong evidence that all patients with OA should be offered adequate education and exercises as a first-line treatment, an effective self-management program, including structured education and therapeutic exercises, has not yet been introduced for individuals with wrist OA. This trial aims to evaluate the effectiveness of an exercise therapy program with joint protective strategies to improve neuromuscular control (intervention group) compared to a training program with range of motion exercises (control group). METHODS: This is a single-blinded randomized controlled trial (RCT) with two treatment arms in patients with symptomatic and radiographically confirmed wrist OA. The trial will be conducted at a hand surgery department. The participants will be randomly assigned either to a neuromuscular exercise therapy program or to a training program with range of motion exercises only. Participants in both groups will receive a wrist orthosis and structured education on wrist anatomy, pathophysiology, and joint protective self-management strategies. The programs consist of home exercises that will be performed twice a day for 12 weeks. The Patient-Rated Wrist Evaluation (PRWE) is the primary outcome measure of pain and function. Wrist range of motion (ROM), grip strength, the Numeric Pain Rating scale (NPRS), Disabilities of the Arm, Shoulder, and Hand (DASH), the General Self-Efficacy Scale (GSES), Global Rating of Change (GROC), and conversion to surgery are the secondary measures of outcome. Assessments will be performed at baseline and at 3, 6, and 12 months after baseline by a blinded assessor. DISCUSSION: The upcoming results from this trial may add new knowledge about the effectiveness of a self-managed exercise therapy program on pain and function for individuals with wrist OA. If the present self-management program proves to be effective, it can redefine current treatment strategies and may be implemented in wrist OA treatment protocols. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05367817. Retrospectively registered on 27 April 2022. https://clinicaltrials.gov .

Evaluation of a newly designed deep learning-based algorithm for automated assessment of scapholunate distance in wrist radiography as a surrogate parameter for scapholunate ligament rupture and the correlation with arthroscopy.

PURPOSE: Not diagnosed or mistreated scapholunate ligament (SL) tears represent a frequent cause of degenerative wrist arthritis. A newly developed deep learning (DL)-based automated assessment of the SL distance on radiographs may support clinicians in initial image interpretation. MATERIALS AND METHODS: A pre-trained DL algorithm was specifically fine-tuned on static and dynamic dorsopalmar wrist radiography (training data set n = 201) for the automated assessment of the SL distance. Afterwards the DL algorithm was evaluated (evaluation data set n = 364 patients with n = 1604 radiographs) and correlated with results of an experienced human reader and with arthroscopic findings. RESULTS: The evaluation data set comprised arthroscopically diagnosed SL insufficiency according to Geissler's stages 0-4 (56.5%, 2.5%, 5.5%, 7.5%, 28.0%). Diagnostic accuracy of the DL algorithm on dorsopalmar radiography regarding SL integrity was close to that of the human reader (e.g. differentiation of Geissler's stages ≤ 2 versus > 2 with a sensitivity of 74% and a specificity of 78% compared to 77% and 80%) with a correlation coefficient of 0.81 (P < 0.01). CONCLUSION: A DL algorithm like this might become a valuable tool supporting clinicians' initial decision making on radiography regarding SL integrity and consequential triage for further patient management.

Limited intercarpal fusion versus proximal row carpectomy in the treatment of SLAC or SNAC wrist, results after 3.5 years.

The present study compares the postoperative clinical, radiological, and patient-reported functional results between the surgical procedures Proximal Row Carpectomy and Limited Carpal Fusion, in the treatment of SLAC and SNAC conditions of the wrist. 15 Proximal Row Carpectomy patients and 45 Limited Carpal Fusion patients were included in the study. Postoperative outcomes were assessed and compared for pain at load, range of motion, grip strength, Quick-DASH, and satisfaction. A radiological assessment was performed at the follow-up. The Proximal Row Carpectomy patients had a mean age of 60 years (range 31-77) and a mean follow-up of 42 months. The Limited Carpal Fusion patients had a mean age of 58 years (range 35-76) and a mean follow-up of 41 months. The patients treated with Limited Carpal Fusion performed significantly better regarding pain, radial-ulnar motion, and the Quick-DASH (p = 0.002, p = 0.003, and p = 0.002), respectively. The grip strength difference between the treatment groups was stratified for gender and was found significantly better for men in the LCF-treated patients, but not different for women (p = 0.03, p = 0.26), respectively. Differences in flexion-extension between the groups were insignificant (p = 0.525). A higher conversion rate to total wrist fusion was observed in the patients treated with the Proximal Row Carpectomy. All the Proximal Row Carpectomy patients had osteoarthritis at follow-up, whereas it was seen in 19% of the Limited Carpal Fusion patients. The patient-reported satisfaction was substantially better for the Limited Carpal Fusion patients. In conclusion, among patients treated for SNAC and SLAC wrist conditions, besides the findings of flexion-extension, and grip strength which were found without difference for women the findings are in favour of Limited Carpal Fusion compared to Proximal Row Carpectomy. Further, preferably prospective studies are needed to confirm or reject our findings.Level of evidence: Retrospective, comparative cohort study, level III.

Scapholunate Instability: Diagnosis and Management - Classification and Treatment Considerations - Part 2.

Intervention for scapholunate instability is aimed at halting the degenerative process by restoring ligament integrity and normalizing carpal kinematics. Part 1 of this Current Concepts article reviewed the anatomy, kinematics, and biomechanical properties of the scapholunate ligament as well as its critical stabilizers. In this section, we provide a foundation for understanding the spectrum of scapholunate ligament instability and incorporate meaningful new anatomical insights that influence treatment considerations. These updates clarify the importance of the critical stabilizers of the scapholunate interval, ligament-specific considerations in scapholunate ligament reconstruction, and the risks of ligament disinsertion when surgically exposing the dorsal wrist. We propose a ligament-based treatment algorithm based on the stage of injury, degree and nature of ligament damage, and presence of arthritic changes.

A project-oriented biochemistry laboratory for protein engineering and structure-function using small laccase enzyme from Streptomyces coelicolor.

An understanding of structure-function relationships in proteins is essential for modern biochemical studies. The integration of common freely accessible bioinformatics tools available online with the knowledge of protein-engineering tools provide a fundamental understanding of the application of protein structure-function for biochemical research. In order for students to apply their prior knowledge of recombinant protein technology into the understanding of protein structure-function relationships, we developed a semester-long project-oriented biochemistry laboratory experience that is the second laboratory course of a series. For easier integration of knowledge and application, we organized this course into four sequential modules: protein structure visualization/modification, mutagenesis target identification, site-directed mutagenesis, and mutant protein expression, purification, and characterization. These tasks were performed on the protein small laccase (SLAC) that was cloned and characterized by students in the previous semester during the first biochemistry laboratory course of the series. This goal-oriented project-based approach helped students apply their prior knowledge to newly introduced techniques to understand protein structure-function relationships in this research-like laboratory setting. A student assessment before and after the course demonstrated an overall increase in learning and enthusiasm for this topic.

Scapholunate Instability: Diagnosis and Management - Anatomy, Kinematics, and Clinical Assessment - Part I.

Injuries to the scapholunate joint are the most frequent cause of carpal instability. The sequelae of these injuries account for considerable morbidity, and if left untreated, may lead to scapholunate advanced collapse and progressive deterioration of the carpus. Rupture of the scapholunate interosseous ligament and its critical stabilizers causes dyssynchronous motion between the scaphoid and lunate. Additional ligament injury or attenuation leads to rotary subluxation of the scaphoid and increased scapholunate gap. Intervention for scapholunate instability is aimed at halting the degenerative process by restoring ligament integrity and normalizing carpal kinematics. In the first section of this review, we discuss the anatomy, kinematics, and biomechanical properties of the scapholunate ligament as well as its critical ligament stabilizers. We provide a foundation for understanding the spectrum of scapholunate ligament instability and incorporate meaningful new anatomical insights that influence treatment considerations. The purpose is to provide an update regarding the anatomy of the scapholunate ligament complex, importance of the critical ligament stabilizers of the proximal carpal row, introduction of safe technique to surgically expose the scaphoid and lunate, as well as pathoanatomy as it pertains to the treatment of scapholunate dissociation. In the second section of this review, we propose a novel ligament-based treatment algorithm based on the stage of injury, degree and nature of ligament damage, and presence of arthritic changes.

Use of Wrist Denervation in the Treatment of SLAC and SNAC Wrist by ASSH Members.

Background Scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) are common patterns of wrist arthritis, and surgical treatment options include partial and total wrist arthrodesis and wrist denervation, which maintains the current anatomy while relieving pain. Introduction The purpose of this study is to elucidate current practices within the hand surgery community with respect to the use of anterior interosseous nerve/posterior interosseous nerve (AIN/PIN) denervation in the treatment of SLAC and SNAC wrists. Methods An anonymous survey was distributed to 3,915 orthopaedic surgeons via the American Society for Surgery of the Hand (ASSH) listserv. The survey collected information on conservative and operative management, indications, complications, diagnostic block, and coding of wrist denervation. Results In total, 298 answered the survey. 46.3% ( N = 138) of the respondents used denervation of AIN/PIN for every SNAC stage, and 47.7% ( N = 142) of the respondents used denervation of AIN/PIN for every SLAC wrist stage. AIN and PIN combined denervation was the most common standalone procedure ( N = 185, 62.1%). Surgeons were more likely to offer the procedure ( N = 133, 55.4%) if motion preservation had to be maximized ( N = 154, 64.4%). The majority of surgeons did not consider loss of proprioception ( N = 224, 84.2%) or diminished protective reflex ( N = 246, 92.1%) to be significant complications. 33.5%, 90 respondents reported never performing a diagnostic block prior to denervation. Conclusion Both SLAC and SNAC patterns of wrist arthritis can result in debilitating wrist pain. There is a wide range of treatment for different stages of disease. Further investigation is required to identify ideal candidates and evaluate long-term outcomes.